well, i ordered a new tvv because the nipples were broken off the old one. it was easy to get the old one out, but a major pia to get the new one in; i ended up breaking the nipples off the new one. so what i did was extend it up with a 3/8" pipe nipple and coupler. i was then able to thread the tvv in easily. i repaired the broken tvv with a ball point pen tube and some silicone. here's some pics.